Existing literature on radical organizational change represented by Plowman, Baker, Beck, Kulkarni, Solansky, and Travis (2007) indicates that continuous emergent process occurring unintentionally causes radical organizational change. Prior literature has not examined the possibility of this process occurring through strong leadership in major inertia, however, Machida (2017) demonstrates this process in the case of Yokohama City. This research aims to indicate two points: First, the causes of continuous emergent process occurring through strong leadership in major inertia through a cross-case comparison analysis of Yokohama City and X City. Second, a new model on radical organizational change, which combines the process indicated through the cross-case comparison analysis and existing literature.